Individuals often find themselves requiring one or more dental prostheses during their lifetime. These prostheses can take the form of complete or partial dentures, crowns, or bridges. They may also take the form of hybrid prostheses which incorporate one or more elements of the aforementioned prostheses. Traditionally, dentistry has provided removable complete and partial dentures, crowns, and fixed bridges to solve the problem of missing teeth. To address issues associated with these traditional approaches, implant-based approaches have evolved to supplement and improve traditional prostheses. These implants may be either of the two-piece or one-piece variety. The two-piece implants have a multitude of abutment heads that can be switched to provide solutions to a variety of prosthetic situations. However, one-piece dental implants are fabricated with only one fixed head, limiting their use. One-piece dental implants, such as those with small diameters or mini dental implants, are often the only implants usable in areas of narrow bone or areas with space considerations. For a review of some advantages of mini dental implants, see “A Periodontal Perspective of Mini Dental Implants”, [Haralampopoulos H A, Haralampopoulos N H. A Periodontal Perspective of Mini Dental Implants. JIAMDI. 2012; Fall:12-19.], which is hereby incorporated by reference in its entirety. It is known in the art that one-piece dental implants are one of the implant-based approaches often used. The one-piece dental implant provides for an abutment head on one end and a screw or fixture on the other end designed to enter the jawbone, both thereby stabilizing the attached prostheses. At least one drawback to one-piece dental implants is that one is unable to easily place, remove, repair or replace the attached prostheses without damaging the prostheses when permanently cemented, which may cause substantial discomfort and expense to the patient as well as inconvenience for both the patient and the provider.
It is the object of the present invention to provide a conversion abutment that will convert the use of a one-piece dental implant into one in which the prosthetic attachment may be affixed by screw or other securing means making the prosthesis retrievable, thus allowing for the initial placement, the removal, the repair, or the replacement of the prosthetic attachment or to provide additional fixed-retrievable prosthetic options, such as fixed-detachable hybrid prostheses, currently used in two-piece dental implant systems, but currently unavailable for one-piece dental implants, thus expanding the use of one-piece dental implants.
Existing one-piece dental implants tend to have features that make repairing, replacing or removing fixed prostheses inconvenient. For example, most commercially available implants provide for a jaw-affixed portion, the implant body, which is typically secured to the patient's jaw using a screw or cylinder with bone growing onto the surface of the implant. The two-piece implants are usually wider in diameter, usually greater than 3 mm, and may have a variety of abutment heads that can be screwed directly into the implant body, chosen to solve a variety of prosthetic treatments. The problem with one-piece dental implants is that the abutment head is not removable and can only be used in a limited choice of prosthetic treatment options. Therefore, the prostheses are attached to the abutment head portion of the jaw-affixed implant by cement or by using an abutment or part specifically designed for the one-piece abutment head. The downside to this type of construction is that permanently fixed complete and partial dentures, hybrids, crowns, and bridges cannot be easily retrieved when used with one-piece dental implants. If a prosthesis becomes damaged or worn or if an implant fails, requiring repair or replacement, one would likely have to damage or destroy the existing prosthesis in order to repair or replace the prosthesis or to have access to treat or remove a failing implant.
Currently in the prior art, there are a number of one-piece implants which are designed to allow for the implantation of various dental prostheses. For example, U.S. Pat. No. 7,108,511 discloses an implant system which comprises a mini dental implant with an abutment end. The abutment end is adapted to allow for the attachment of the dental crown of a prosthetic tooth. However, in this system, the fixation of the crown or prosthesis is performed with dental cement, and is thus permanent and irreversible without destroying the prosthesis or the dental implant itself.
U.S. Pat. No. 8,043,089 discloses a one-piece dental implant that comprises an elongated implant body that screws into the jawbone, a keeper cap which can be affixed to the implant by an O-ring-shaped insert and allows for increased stability. However, the one-piece implant described therein does not allow for a screw-based fixation to the implant body and is only used for removable prostheses.
Additional references describe various one-piece implants, including U.S. Pat. Nos. 8,118,596, 8,277,218, U.S. Pub. No. 2011/0117522 and U.S. Pub. No. 2011/0223561.
None of the above inventions and patents, taken either individually or in combination, describes the subject of the instant invention.